Inorganic Salt NaCl Research Articles

Effect of fluorocarbons and inorganic salts on wetting and foaming characteristics of hydrocarbon surfactants

To improve the wetting and foaming properties of anionic SDS foam on coal dust, we experimentally investigated the effects of short-chain fluorocarbon surfactant FS-50 and inorganic salt NaCl on the wetting and foaming properties of SDS foam and the synergistic effect of the mixed system. The experimental results show that SDS and FS-50 can effectively improve the wetting properties of coal dust in a concentration of 0.05–0.16 wt% and a ratio of 3:1–1:2. In the mixed system, SDS provides sufficient hydrophilic base, FS-50 can effectively reduce the surface tension and have a certain agglomeration effect on coal dust to accelerate the settlement of coal dust and improve the wetting properties of coal dust. When the mixed ratio is lower than 1:1, the foaming volume and foam half-life of the surfactant solution are significantly reduced. The number of SDS molecules at the solution gas-liquid interface is reduced due to electronegative repulsion, and the FS-50 replenishes to the liquid surface faster due to stronger hydrophobicity, and it is difficult to form hydrogen bonds with water molecules, which reduces the foam stability. Low concentrations of inorganic salts can significantly improve the wetting performance of the SDS/FS-50 mixed system to coal dust, and high concentrations will reduce the foam stability of the mixed system.

Molecular dynamics study on the effect of inorganic salts on the wettability of surfactants on bituminous coal: Sodium dodecyl sulfate and sodium chloride as representatives

To further enhance the wetting ability of surfactants to coal, the mechanism of improving the wetting performance of SDS to bituminous coal by the addition of inorganic salt NaCl was studied through a combination of molecular dynamics (MD) simulation with experimental measurements. In the experiment part, the surface tensions of the mixed NaCl-SDS solutions and the contact angles on the bituminous coal surface were measured. Furthermore, MD simulations were conducted to investigate the adsorption characteristics and wetting mechanism of a mixed NaCl-SDS solution on the coal surface at the atomic scale. In this process, the static potentials of the H2O molecule, coal molecule and SDS molecule were calculated, and the number of hydrogen bonds (H-bonds) formed throughout the whole simulation process, the average H-bond length, the relative concentration distribution (RCD) curve and the mean square displacement (MSD) curve were obtained. The experimental results showed that the surface tension and contact angle were both decreased by the addition of sodium chloride in mixed solutions. When 0.6 mol/L NaCl was added, the surface tension and contact angle reached the minima of 30.45 mN/m and 13.01°, respectively. The MD simulation results showed that, after the addition of NaCl, diffusion and migration of H2O molecules were limited, the number of H-bonds increases, the average bond length decreased, the sorption between H2O molecules and coal molecules was enhanced, and the hydrophilicity of coal surface was improved, which meant that the wetting ability of SDS solution to bituminous coal was enhanced by adding NaCl. The effect of the added NaCl in improving the wettability of SDS on coal was explored from two perspectives with macroscopic experiments and microcosmic simulations, and the added NaCl improved the effects of dust suppressants, and played a key role in preventing dust hazards in coal mines.

The effect of inorganic salt on the morphology and nucleation of polyaniline nanofibers synthesized via self-assembly

ABSTRACTPolyaniline (PANI), due to the various and controllable shapes, the environmental stability, the excellent physical and chemical property, has gained significant attention. PANI with abundant morphologies were successfully prepared through adjusting and controlling the state of the initial micelle-like in the micelle-like system composed by aniline and organic acids with relatively weak intermolecular interaction. Although the influence of the inorganic salts on their morphology, including the surface and the diameter, was investigated, the influence of salt on the nucleation of PANI was still unclear. Therefore, PANI nanofibers were fabricated through the addition of inorganic salt such as NaCl, MgSO4 and AlCl3 into the micelle-like composed of aniline and D-camphor-10-sulfonic acid. The influence of types and concentration of inorganic salts, doped acids and temperature on PANI was studied by Transmission Electron Microscope (TEM), UV-vis and Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy. In addition, in situ UV-vis and 1H Nuclear Magnetic Resonance technology (NMR) were applied to observe the process of aniline polymerization, and it was indicated the polymerization rate of aniline changed after the addition of inorganic salt NaCl into the initial solution.

Thermophysical properties of 1-butyl-3-methylimidazolium octyl sulfate ionic liquid in aqueous and aqueous electrolyte solutions at different temperatures

Understanding the molecular interaction of 1-butyl-3-methylimidazolium octyl sulfate i.e., [Bmim][OcOSO3] in water and in aqueous NaCl solution is important for fabricating the new process. As it is already known that ionic liquids along with inorganic salt NaCl have significant potential in the tribology of lubricants and salting-out media for the separation of nicotine. It is known that ionic liquids exhibit characteristic behavior at solid−liquid interfaces. Although it is believed that the structure of ionic liquids at the interface contributes to the tribological properties in the region of boundary-mixed lubrication, this contribution has not been clarified yet. Thus, we study the molecular interaction of the ionic liquid in aqueous and ionic liquid in aqueous NaCl solutions through the thermodynamic approach. We have measured density as an important parameter for 1-butyl-3-methylimidazolium octyl sulfate i.e., [Bmim][OcOSO3] in water and in aqueous NaCl solution within the concentration range of 0.04-0.12 mol/kg at different temperatures i.e. 293.15, 298.15, 303.15, 308.15, and 313.15 K and atmospheric pressure by using a densitometer (DSA5000M Anton Paar). The density (ρ) data were employed to measure some derived parameters such as apparent molar volume of solute (Vϕ), limiting apparent molar volume of solute (Vϕ0), thermal expansion coefficient (α), apparent molar expansivity of solute at finite concentration (Eϕ) and at infinite concentration (Eϕ0) and transfer volume (ΔtrVϕ0). Results have been discussed in terms of all the possible molecular interactions in systems.

Experimental Research on the Performance of a Wetting Agent Based on Compound Acidification in Low-Porosity and Hard-to-Wet Coal Seams.

To improve the wetting performance of the composite acid solution in the deep coal seam, in this paper, the surface tension and contact angle characteristics of the compound acid wetting agent are studied, then the composition of the wetting agent is developed and evaluated based on nuclear magnetic resonance. The research indicates that surfactants can reduce the surface tension of water, and the surface tension tends to decrease with the increase in the surfactant concentration. The critical micelle concentration of the anionic surfactant sodium dodecyl sulfate (SDS) solution is only 0.025%, and the corresponding critical surface tension is 30.63 mN/m. The wetting agent material based on the composite acid solution includes the acid HCl, HF, the anionic surfactant SDS, and the inorganic salt NaCl, the composition of which is 8%, 8%, 0.025%, and 0.6 mol/L, respectively. The total wetting rate of the composite acid-containing HCl + HF + SDS + NaCl is the largest, reaching 64.30%, which has good wettability inside the coal and can be a comprehensive intrusion into the internal structure of coal pores.

Characterization, application and statistical optimization approach for enhanced production of pyocyanin pigment by Pseudomonas aeruginosa DN9

The aim of this work was to study the pyocyanin pigment from Pseudomonas aeruginosa DN9. The work involves optimization of process parameters for enhanced production of pyocyanin pigment under submerged fermentation condition. During optimization process, maximum pyocyanin production (92.12 µg/ml) was obtained with carbon source mannitole, nitrogen source peptone, inorganic salt NaCl and metal ion FeSO4. Plackett Burman design and Response Surface Methodology (RSM) showed peptone, NaCl and KH2PO4 are significant variable in the production of pyocyanin pigment. The FTIR and GC–MS study was done to evaluate structural properties of pyocyanin pigment. The purified pigment was further analyzed as colouring agent and for inhibitory action against pathogenic microorganisms. Thus, present study showed Pseudomonas aeruginosa DN9 as promising culture for pigment production with potential biotechnological application.

Preparation of Lignite Dust Suppressant by Compound Surfactants and Effect of Inorganic Salt on Dust Suppressant

In order to improve the safety, operability, and cleanability of the dust suppressant, this paper uses the surfactant monomers selected in the previous experiment as the main material formula and adds the inorganic salt as the synergist to prepare the dust suppressant for the PMX. The wetting property of the solution was characterized by the surface tension and contact angle of the pressed coal pieces. The sedimentation experiment was used to screen the compounding system of the surfactant. Finally, the dust suppressant was used to reduce the dust of the PMX in the coal dust simulation system. The results show that (1) the surfactant compounding system can effectively improve the wetting property and the sedimentation time of coal dust. The fast penetration T (0.06%), SDBS (0.15%), and APG (0.20%) are the preferred main ingredients. (2) Adding inorganic salts on the basis of compounding, according to the effect of inorganic salts on the effect of dust suppressant, it is concluded that NaCl (1.00%) is the best synergist. (3) In order to save costs, reduce the amount of surfactant. According to the simulated dust reduction experiment, formula N: anionic surfactant SDBS (0.06%), anionic surfactant fast‐permeability T (0.06%), and inorganic salt NaCl (1.00%) are the best for PMX dust fall.

Effect of Salinity and PH on the Industrial Effluent Treatment by Activated Carbon: Modeling of the Kinetic Adsorption and Equilibrium Isotherms

In recent years, interest has been focused on the removal of phenols from contaminated by using a variety of purification techniques. Adsorption of bio-industrial effluent on commercial activated carbon S23 was investigated at ambient conditions. In this wok, phenol and p-hydroxyl benzoic acid (PHBA) was studied as an example of the organic compounds present in the industrial effluent. The effect of temperature, pH, and the presence of inorganic salt NaCl on the pollutants adsorption were studied to give further comprehension of the optimal conditions of the organic compounds adsorption onto activated carbon. It was noted that the increase in temperature resulted in a decrease in phenols adsorption capacity by S23. Lower phenol adsorption was also observed at the solution pH 2 and 10, whereas, favourable adsorption was reached at neutral solution pH, and the coexisting inorganic salt NaCl exerts slightly positive effect on the adsorption process. The isotherms obtained at pH 2.2 and 3.5 (non-buffered solution) are very similar and showed a higher adsorption capacity compared with that obtained at pH 7 and 10 for PHBA which is more adsorbable than phenol. The kinetic of the adsorption processes can be better represented by the pseudo-second order. The results showed also that the total organic carbon (TOC) of the industrial effluent reduced for about 20 %. Freundlich, Langmuir and Jovanovic adsorption models were used for mathematical description of adsorption equilibrium of phenols. The results showed that the experimental data fitted very well to the Freundlich and Jovanovic models.

The great improvement of the surfactant interfacial activity via the intermolecular interaction with the additional appropriate salt

The typical organic salt benzyltrimethylammonium bromide (BMAB) was used to greatly enhance the interfacial activity of the traditional anionic surfactant sodium dodecyl benzene sulfonate (SDBS). The additional BMAB caused the obvious reduction of the interfacial tension (IFT) between the SDBS aqueous solution with a low concentration and model oil (Vtoluene:Vn-decane = 1:1). Based on the special SDBS/BMAB intermolecular interaction, we proposed that the synergistic effect between the electrostatic attraction and π-π stacking interaction largely increased the SDBS interfacial concentration, leading to the dramatic IFT reduction. Three organic salts and two surfactants with similar structures, as well as the typical inorganic salt NaCl, were used in control experiments to confirm our speculation. The interaction energies between SDBS molecules and different organic salts were calculated using molecular mechanics to further interpret the mechanism. The salt and temperature tolerances of the SDBS/BMAB system were systematically investigated. Moreover, the availability of the SDBS/BMAB mixture in brine water/crude oil system was evaluated by the core flooding tests.

Facile fabrication of gelatin/bentonite composite beads for tunable removal of anionic and cationic dyes

The gelatin/bentonite composite beads (Gel–Bent) were facilely prepared by compacting gelatin and bentonite and characterized using scanning electron microscopy, X-ray diffraction, fourier transform infrared spectra, thermogravimetric analysis and Zeta potential. The tunable adsorption property of Gel–Bent toward the anionic dye (congo red (CR)) and cationic dye (methylene blue (MB)) was investigated by changing the mass ratio of bentonite to gelatin. The effect of contact time, temperature and pH on the adsorption of CR and MB onto Gel-12.5%Bent (12.5% of Bent in amount of Gel) was investigated. Its selective adsorption property in the MB/CR binary system was evaluated under the co-presence of anionic surfactant SDS and inorganic salt NaCl at various pHs. Three isotherm models in linear and non-linear regressions, and two kinetic models were employed and assessed by various error functions. In addition, the swelling behavior of the composite beads was studied and the possible adsorption mechanism was also proposed. All the information indicated that Gel–Bent was expected to be a promising candidate for efficient removal of anionic and cationic dyes.

Aerosol-Assisted Rapid Fabrication of a Heterogeneous Organopalladium Catalyst with Hierarchical Bimodal Pores.

Heterogeneous organometallic catalysts with well-defined active sites and hierarchical pores hold tremendous promise for efficient and eco-friendly chemical processes. However, the simple and scalable preparation of these materials remains difficult to date, which has hampered a more broad application scope. Herein, we reported a low-cost, rapid, and scalable aerosol-assisted assembly approach for the synthesis of a well-defined PdDPP (PdCl2(PPh2(CH2)2))_ complex-containing benzene-bridged organosilica-based catalyst with a hierarchical bimodal micro-macroporous structure. This novel material was realized by using Pd(II) organometallic silane (Pd[PPh2(CH2)2Si(OEt)3]2Cl2) as the active species, organosilane 1,4-bis(triethoxysilyl)benzene (Ph[Si(OEt)3]2) as the silicate scaffold and the surfactant cetyltrimethylammonium bromide and the inorganic salt NaCl as the dual templates on a home-built aerosol spraying-instrument. Multiple techniques including X-ray photoelectron spectroscopy and solid-state NMR spectra revealed that the organopalladium complex with a well-defined molecular configuration of major trans model and minor cis model existed in the phenyl-functionalized silica material. As expected, it efficiently promoted a variety of important carbon-carbon cross-coupling transformations including Tsuji-Trost, Sonogashira, and Suzuki reactions in pure water without the assistance of any additives. In comparison with the homogeneous catalyst PdCl2(PPh2CH3)2, it even exhibited enhanced activity and selectivity in some cases owing to the unique confinement effect and the shape selectivity generated from the hierarchical porous structure. Meanwhile, it was easily recycled and reused eight times without the loss of its activity.

Tight ultrafiltration membrane: Preparation and characterization of thermally resistant carboxylated cardo poly (arylene ether ketone)s (PAEK-COOH) tight ultrafiltration membrane for dye removal

Cardo poly (arylene ether ketone)s bearing hydrophilic carboxylic acid groups (PAEK-COOH) was successfully synthesized by condensation polymerization of 2-[bis(4-hydroxyphenyl)methyl] benzoic acid and 4,4′-bisfluorodiphenylketone. TGA and DSC analyses demonstrated that the material has an initial decomposition temperature and glass transition temperature of 360°C and 220°C respectively, which revealed the excellent thermal stability of PAEK-COOH. Then PAEK-COOH was employed to fabricate tight ultrafiltration membrane by the nonsolvent induced phase inversion process (NIPS). The water contact angle of the prepared membrane is 61.5°, indicating its good hydrophilicity. The PAEK-COOH tight ultrafiltration membrane possesses a pure water flux of 119.6±2.6Lm−2h−1, dye permeation flux of 100.9±4.3Lm−2h−1 and rejection of 99.8±0.33% for Congo red at dye concentration of 100ppm and operation pressure of 0.4MPa. Membrane has a molecular weight cut off of 9260Da and gives complete penetration of monovalent inorganic salt NaCl but a slight rejection of divalent inorganic salt Na2SO4 (less than 10%). Thus, the membrane could be used in the decolorization of wastewater or fractionation of dye and salt mixture for dye purification. The membrane also exhibits excellent antifouling performance and anti-dye adsorption properties with a flux recovery ratio of 91.5% for BSA and dye adsorption rate below 5.0% for four kinds of studied dyes, respectively.

Biosorption performances of raw and chemically modified biomasses from Perenniporia subacida for heterocycle dye Neutral Red

Biosorption performances of raw and chemically modified biomasses (treated with (i) lipid removal, (ii) phosphate esterification, (iii) amine methylation, and (iv) amine propylamination) from white rot fungus Perenniporia subacida were investigated for heterocycle dye Neutral Red removal. Better dye uptake was obtained at constant temperature and agitation speed with the optimum variables like initial pH at 3.0, initial dye concentration at 50 mg/L, surfactant Tween 80 at 2.5% (V/V), inorganic salt NaCl at 0.1 M, and first 60 min of reaction time. A comparison of the different isotherm models indicated that the biosorption process by the fungal biomass followed the Langmuir isotherm model. The kinetic data could be well described by the pseudo-second-order model. Calculated thermodynamic parameters of biosorption indicated the exothermic and spontaneous process. Additionally, the modification of biomass with amine propylamination increased the biosorption capability of Neutral Red dye about 1.36-fold of the raw fungal biomass. These observations were characterized by FT-IR, SEM, and X-ray diffraction, respectively.

A water–ethanol phase assisted co-precipitation approach toward high quality quantum dot–inorganic salt composites and their application for WLEDs

Aqueous CdTe QDs embedded in inorganic salt NaCl through a co-precipitation approach assisted by ethanol are synthesized.

Plugging behavior of gellan in porous saline media

ABSTRACTIn this article, the hydrodynamic behavior of dilute aqueous solutions of a natural polysaccharide—gellan in the porous media under the modeled oilfield conditions is described. The hydrodynamic properties of gellan and poly(acrylamide) solutions in saline porous media are compared. The influence of inorganic salts NaCl, KCl, CaCl2, MgCl2, and BaСl2 on sol–gel and gel–sol transitions of dilute gellan solutions was evaluated. The mechanism of sol–gel transition in the presence of individual alkaline and alkaline‐earth metal salts is described on the basis of literature data. The viscometric measurements revealed that the effectiveness of salts to enhance gelation of gellan changes in the following order: BaСl2 > CaCl2 ≈ MgCl2 > KCl > NaCl. The sol–gel and gel–sol phase transitions of gellan solution were also observed upon addition of oil field water containing 73 g L−1 of alkaline and alkaline earth metal ions. During the injection of gellan solutions into the porous media saturated by saline water an oscillation of the injection pressure was observed. Such behavior of gellan is explained by either the sol‐to‐gel and the gel‐to‐sol transitions of the polymer taking place in saline water or the step‐by‐step plugging of high permeable channels until all high permeable channels of sand packs are plugged due to gellan invasion. The application of brine‐initiated gelation of gellan for water shutoff operations (WSO) in field conditions was demonstrated. Higher technological effectiveness of gellan injection in comparison with existing gelation systems was shown. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41256.

Rheological properties of hydrolyzed polyacrylamide/sodium oleate mixed system in the presence of different inorganic salts

Abstract The effects of inorganic salts NaCl, KCl, CaCl2 and MnCl2 with the same anions but different cations on the rheological properties of hydrolyzed polyacrylamide/sodium oleate (HPAM/C17H33COONa) mixed system were investigated systemically by steady-flow and oscillatory experiments at different concentrations of inorganic salts and temperatures, respectively. The results of steady-flow measurements indicate that for all of the systems, the steady-shear viscosities (η) decrease obviously with the addition of inorganic salts and show shear-thinning property at higher shear rate and the data fit power-law equation. In oscillatory experiments, all of the systems show elastic behaviors which also depend strongly on the concentrations of the inorganic salts. The storage moduli (G'), loss moduli (G″), the complex viscosities (η⁎) and η all decreased as the inorganic salts concentrations increased. The order of effectiveness of cations in decreasing the viscosity and the activation energy of HPAM/C17H33COONa mixed system is Na+>K+> 1 2 Ca2+> 1 2 Mn2+.

Inorganic Salts Effect on Adsorption Behavior of Surfactant AEC at Liquid/Liquid Interface

Behaviors of nonionic-anionic surfactant sodium fatty Alcohol polyoxyethylene Ether Carboxylate (AEC) at dodecane/water interface influenced by inorganic salts NaCl, CaCl 2 and MgCl2 were investigated by interfacial tension methods and molecular dynamics simulation. Contrasted distributions of various salts at interface and in aqueous solutions and resulting lowering the interfacial tension have been observed. Composition of surfactants- salts complex at interface surrounding different cations within 2.5 A were found to be in two categories: (i) the octahedral complexation of divalent cation was generated by the participation of surfactant head group and water molecule, (ii) only water molecules were involved in the complexation. According to the simulation results, all the Na + involved in type ii, without any direct interaction with surfactant head group, while Ca 2+ and Mg 2+ involved in type I, following the formula: Ca+ + 4 (surfactant) + 2 (H2O) ⇄ (Ca (surfactant) 4 (H2O) 2) 2+ , Mg 2+ + (surfactant) + 5 (H2O) ⇄ (Mg (surfactant) (H2O) 5) 2+ . This strongly chelate interaction between Ca 2+ and

Surface Activity Research of Cationic Gemini Surfactants

Cationic Gemini surfactant concentration, the inorganic salts added and the pH value of surface tension obtained cationic gemini surfactant critical micelle concentration is 0.4mmol / L;by adding three kinds of inorganic salts NaCl, MgCl2, and Na2SO4 ,which Na2SO4 has the greatest impact on surface tension, followed by MgCl2.The surface minimum tension of the pH ranged from 9 to 11 , indicating that the surface activity of cationic gemini surfactants achieved the highest.

Surface Activity Research of Cationic Gemini Surfactants

Cationic Gemini surfactant concentration, the inorganic salts added and the pH value of surface tension obtained cationic gemini surfactant critical micelle concentration is 0.4mmol / L;by adding three kinds of inorganic salts NaCl, MgCl2, and Na2SO4 ,which Na2SO4 has the greatest impact on surface tension, followed by MgCl2.The surface minimum tension of the pH ranged from 9 to 11 , indicating that the surface activity of cationic gemini surfactants achieved the highest.

Adsorptive removal of phenol from aqueous phase by using a porous acrylic ester polymer

The removal of phenol from aqueous solution was examined by using a porous acrylic ester polymer (Amberlite XAD-7) as an adsorbent. Favorable phenol adsorption was observed at acidic solution pH and further increase of solution pH results in a marked decrease of adsorption capacity, and the coexisting inorganic salt NaCl exerts positive effect on the adsorption process. Adsorption isotherms of phenol were linearly correlated and found to be well represented by either the Langmuir or Freundlich isotherm model. Thermodynamic parameters such as changes in the enthalpy (Δ H), entropy (Δ S) and free energy (Δ G) indicate that phenol adsorption onto XAD-7 is an exothermic and spontaneous process in nature, and lower ambient temperature results in more favorable adsorption. Kinetic experiments at different initial solute concentrations were investigated and the pseudo-second-order kinetic model was successfully represented the kinetic data. Additionally, the column adsorption result showed that a complete removal of phenol from aqueous phase can be achieved by XAD-7 beads and the exhausted adsorbent was amenable to an entire regeneration by using ethanol as the regenerant. More interestingly, relatively more volume of hot water in place of ethanol can also achieve a similar result for repeated use of the adsorbent.